1. Field of the Invention
This invention generally relates to methods for analyzing milk samples. More specifically, this invention relates to a method and apparatus for calculating the butterfat content in flowing milk.
2. Present State of the Art
For a considerable number of years, farmers have attempted to estimate the quality of the products they produce whether it be grain, potatoes, milk, or livestock. By identifying the best products, they can achieve a higher yield from their efforts, and therefore maximize their profits and minimize waste. To facilitate maximization, farmers may resort to outside experts who will test their products and provide advice based on the test results. For example, in the milk production industry, a dairymen relies on an inspector who travels to their dairy, takes samples from each cow and then returns to a laboratory to test the milk sample for butterfat, protein, lactose, casein or other non-fat solids. There is a lag time of a few days between the removal of a sample from the dairy and the determination of milk component percentages. A better alternative is to have an on-line analyzer which is capable of giving accurate milk component percentages within a short period of time.
Current instrumentation for analyzing milk content does not allow for on-line analysis of milk and, furthermore, employ infrared (IR) technology which has a number of drawbacks. In the prior art approaches, IR radiation is directed at a milk sample and the associated absorption pattern is used to determine the components of the milk. These infrared analyzers require frequent calibration to retain specificity in analysis, especially when calculating a percentage quantity of more complex proteins, like casein. Infrared technology is also commonly employed for evaluation in batch operations, not for in-line analysis.
While the use of infrared techniques in evaluating the butterfat content and other protein contents of milk products is well known, infrared techniques suffer from other short comings including the necessity for frequent calibration of the infrared devices. Furthermore, infrared evaluation devices also require frequent maintenance of the apparatus to maintain adequate optical conditions for testing the milk product. These and other short comings of the infrared and optical systems render them very impractical for use in on-line analysis of butterfat and protein contents as well as for use in an integrated in-line solution for milk product characterization.
Thus, what is needed is a method and apparatus for measuring butterfat content in milk in a near real-time environment capable of processing a substantially larger number of samples of milk products. Furthermore, what is needed is a method and apparatus for evaluating the butterfat content and alternatively protein content in milk products in a timely and in-line manner wherein the evaluation of the characteristics of the milk under test may be performed on a stream of milk rather than in a batch mode process.